Expansion valve



A. F. HOESEL EXPANSION .VALVE Filed Nov. 9. 1925 Feb; 28, 1928.

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UNITED STATES PATENT OFFICE.

ANTHONY F. HOESEL, OF CHICAGO, ILLINOIS, ASSIGNOR '10 PEERLESS ICEMAC-Hm] COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

EXPANSION VALVE.

Application filed November 9, 1925. Serial No. 67,776.

My invention relates, more particularly, to expansion valves for use inrefrigerating systems to control the flow of the refrlgerating agent tothe refrigerating coils, or the like.

My primary object is to provide an expansion valve whereby wire-cuttingof the seat thereof producing erosion will be minimized and the valveoperate automatically to regulate the flow of refrigerant therethroughwhen installed in apparatus having different rated capacities, andregardless of variations in operating capacities of the apparatus towhich it is applied.

In explanation of the above referenceto Wire'cutting it may be statedthat under the great differentials of pressure exlsting between. the lowpressure and high pressure sides of a refrigerating apparatus, the control outlet of a single valve element provided to control the flow ofthe refrigerating agent to the refrigerating coil, is subjected to theaction of the fluid flowing at a great velocity which produces erosionof the valve seatimpairing its function, it being understood that thegreater the differential pressure the greater the velocity of the fluidand consequently the greater the erosion.

I minimized this objection, while maintaining the valve automaticallycontrolled to cause it to properly function in. apparatuses of differentrated capacities and apparatus wherein the operating capacities vary, byproviding for multiple stage reduction of pressure, whereby the velocityof the fluid existing at the controllable outlets of the valve aregreatly reduced, and automatically controlling the operation ofthe valveresponsive to the building up of pressure in the low pressure side ofthe apparatus.

Referring to the accompanying drawing illustrating the preferredembodiment of my invention, the view therein shown represents myimproved valve structure in vertical sectional elevation.

The particular construction of valve illustrated comprises a member 1containing a chamber 2 into which an annular flange 3 of the member 1,depends, the top of this member containing an opening 4 within theconfines of the flange 3; The member 1 contains a passage 5 which opensinto the chamher 2 and which in practice would communicate withthe highpressure side of a refriga'pipe 6 screwed into a head 7 which containsa. passage 8 opening into the passage 5, p

the passage 8 having a valve seat 9 controlled by a manuallycontrollable valve 10. The member 1 also contains a passage 11 openingupwardly through the top thereof as shown and communicating with the lowpressure side of a refrigerating apparatus through the medium of a pipe12 which opens through a passage 13 in a head 14, this passagecontaining a valve seat 15 controlled by a manually controllable valve16.

Secured to the lower end of the member 1 at its chamber portion 2 is ahollow member 17, the recess 18 thereof forming a continuation of thechamber 2, this member being closed at its bottom except for a centrallylocated opening 19 in which a plug20 is screwed.

Screwed at its upper end into the flange 3 and against a gasket, is avalve casing 21 containing in its side wall inlets 22. Secured in thecasing 21 in spaced relation to each other and both above the inlets 22,are tubes 23 and 24:, the opening through the tube 23 being of largerdiameter than the opening through the tube 24, the lower edges of thesetubes forming valve seats-25 and 26 with which reciprocable valves 27and 28 cooperate, respectively. The valve 27 is provided with anupwardly extending stem 29 and at its lower end wit a guide member 30shown as comprising radiating fins which slidingly fit the openingthrough the casing 21 and serve to properly guide the valve in itsmovements, the valve 27 being normally forced into tight engagement withthe seat 25, by a coil spring 31 within the casing 21 and interposedbetween the member 30 and the tube 24:. The valve 28 is of the sameconstruction as the valve 27, its upwardly extending stem beingrepresented at 32, and its depending finned guide portion represented at33. Acoil spring34 located in the casing 21 and interposed between theguide member 33 and the plug 20 operates to normally hold the valve 28against the seat 26, the plug 20 permitting of the removal of valve 28'and spring 34, where desired, without removal of the casing 17.

The unseating of the valve 28, in the operation of the device iseffected throughthe medium of the valve 27 in lowering, the

valve structure 27 however being normally s aced from the upper end ofthe stem 32 of tiie valve 28, when both of these valves are seated, toensure closing of the valve 28, the valve 27 being spaced from the valve28 only to such an extent as will insure the closing of the latter.

It will be understood from the foregomg that the high-pressure from thepipe 6 enters the chamber 2 and thence passes into the 1nterior of thevalve casing 21 through the o enings 22 and out through this casing if te valves 27 and 28 are in open condition, and to intercept foreignmaterial which may be contained in the refrigerating agent, the nestedcircular screens 35 and 36 are provided.

The valve structure described is controlled through the medium ofdiaphragm mechanism the position of which is controlled by the degree ofpressure in the low pressure side of the apparatus. The diaphragmmechanism shown comprises a flexible diaphragm 37 located within achamber 38 provided between the member 1 and a cover member 39 rigidlysecured to the latter, the valve casing 21 and the passage 11 opening attheir upper ends into this chamber, this diaphragm being held in placeat its peripheral edge between the member 1 and the capmember 39 as bymeans of the screws 40. The diaphragm 37 is provided on its upper sidewith a disk 41 between which and a screw 42 vertically adjustable in thetop of the cover 39, a coil spring 43 located within the cover member,extends, this spring operating to force the diaphragm 37 downwardly, thelatter being provided at its underside with a disk 44 which slideswithin guides 45 and cooperates with the upper end of the stem 29.

,The operation of the mechanism is as fol-- lows: The screw 42 havingbeen adjusted to cause the spring 43 to move the valves 27' and 28 toopen condition, upon the accumu- 'lation of a predetermined amount ofpressure in the low pressure side of the refrigerating apparatus, thedropping of such low pressure below the predetermined pressure willresult in the lowering of the diaphragm A 37, which in lowering forcesthe valve 27 downwardly, out of engagement with its seat and by reasonof the engagement of this valve with the valve stem 32 forces the valve28 downwardly from its seat, whereupon pressure from the high pressureside of the apparatus flows upwardly through the differential restrictedoutlets of the valve structure and formed in the sleeves 24 and 23,thence passing into the chamber 38 and downwardly through the passage11' to the low pressure side 12. As soon as the pressure in the lowpressure side has been built up to the desired predetermined degree forwhich the tension of the spring 43 is set, the diaphragm 37 rises to theposition shown in the drawing permitting both of the valves 27 and 28 toseat thereby closing the low pressure side to the high pressure side.

It will be understood that by providing the valve seats 26 and 25 topresent different effective openings, the efl'ectiveopening atthe seat25' being greater than at the seat 26, the pressure existing between thevalve'seats 25 and 26 while less than the pressure in the high pressureside of the apparatus, is greater than the pressure in the low pressureside thereof, and thus the velocity of the refrigerant at both of thesevalve seats is greatly reduced compared with the velocity which occursat the control outlet of a valve employing a single control outlet anderosion of the valve structure is thus minimized.

Furthermore, it will be noted that by con trolling the opening andclosing of the valves 27 and 28 responsive to variations in the pressurein the low pressure side of the apparatus, as through the medium of thediaphragm mechanism shown and described, the valve when installed inrefrigerating systems of different rated capacities, within certainlimits, or when the operating capacities of the apparatuses vary, effectproper automatically regulated control of the flow of 1refrigeratingagent to the refrigerating CO1 s. I

While I have illustrated and described aparticular constructionembodying my invention, I do not wish to be understood as intending tolimit it thereto, as the same may be variously modified and alteredwithout departing from the spirit of my invention.

What I claim as new, and desire to secure by Letters Patent, is:

1. Pressure-reducing valve mechanism comprising a casing containing apassage therethrough having valve seats of different effective openings,the valve seat of larger effective opening being nearest the outlet endof said passage, valves cooperating with said seats, and a singlepressure-responsive device controlling the simultaneous movement of saidvalves, the effective openings of said seats being so proportioned thatsubstantial back pressure exists in the portion of said passage betweensaid valve openings of said seats being so proportioned thatsubstantialback pressure exists in the portion of said passage bet-ween said valveseats to effect multi-stage reduction of the pressure and velocity ofthe fluid flowing through said passage, and said valves being soarranged that pressure applied to one thereof by said device for movingit to 0 en position forces the other thereof open a er the initialmovement of said first-referred to valve to open condition.

3. Pressure-reducing valve mechanism comprising a casing containing apassage theretln'ough havin valve seats of dlfi'ercnt, eflectiveopenings, the valve seatof larger efi'ective opening being nearest theoutlet end of said passage, normally self-closing, valves cooperatingwith said seats, and a single pressure-responsive device controlling thesimultaneous movement of said valves, the eflective openings of saidseats being so proportioned that substant1al back pressure exists in theportlon of said passage between said valve seats to effect multi-stage'reduction of the pressure and velocity of the fluid flowing throughsaidpassage. .4. In refrigerating apparatus, the combination with itslow pressure conduit and high pressure conduit of valve mechanismcontrolling the flow oi fluid from: said high pressure conduit to saidlow pressure conduit comprising a casing containing a passagetherethrough havingvalve seats of different eflective openings, thevalve seat of lar er efl'eetive opening bein nearest the out et endofsaid passage, va ves cooperating with said seats, and a singlepressureresponsive device controlled by the pressure in said lowpressure conduit and controlling the simultaneous movement of saidvalves,

the effective openings of said seats being'so proportioned thatsubstantial back pressure exists in the portion of said passage betweensaid valve seats to effect multl-stage reduction of the pressure andvelocity of the fluid flowing through said passage to said lowpressure'conduit.

ANTHONY F. HOESEL.

